Hadith 40220

Yahya related to me from Malik from more than one source thatwhen Abdullah ibn Masud was in Kufa, he was asked for an opinion aboutmarrying the mother after marrying the daughter when the marriage withthe daughter had not been consummated. He permitted it. When Ibn Masudcame to Madina, he asked about it and was told that it was not as hehad said, and that this condition referred to foster-mothers. IbnMasud returnedto Kufa,and he had just reached his dwelling when theman who had asked him for the opinion came to visit and he ordered himto separate from his wife.Malik said that if a man marriedthe mother of a woman who was his wife and he had sexual relationswith the mother then his wife was haram for him, and he had toseparate from both of them. They were both haram to him forever, if hehad had sexual relations with the mother. If he had not had relationswith the mcther, his wife was not haram for him, and he separated fromthe mother.Malik explained further about the man who marrieda woman, and then married her mother and cohabited with her, "Themother will never be halal for him, and she is not halal for hisfather or his son, and any daughters of hers are not halal for him andso his wife is haram for him."Malik said, "Fornicationhowever, does not make any of that haram because Allah, the Blessed,the Exalted, mentioned 'the mothers of your wives,' as one whommarriage made haram, and he didn't mention the making haram byfornication. Every marriage in a halal manner in which a man cohabitswith his wife, is a halal marriage. This is what I have heard, andthis is how things are done among us."